I'm getting an error whenever I try to authenticate my account. What can I do to solve it.

Resolving this issue is crucial for maintaining accurate bank transactions, and I'm here to assist you in finding a solution, Drlondon.

Beforehand, can you please share the name of the bank account you need to re-authenticate? So I can review any related issues with your bank on my end.

Nonetheless, please know that error 590 typically doesn't last more than 48 hours and should self-resolve on its own. 

However, if the error persists, it may indicate that the 90-day Open Banking authorisation period between your bank and QuickBooks has expired. You can reconnect your account to re-authorise the connection.

To accomplish this, go to your Categorised bank page and note the date of the most recent transaction downloaded. By doing this, you can avoid downloading the same transaction more than once when you reconnect. Before disconnecting your account, please note that QuickBooks deletes the transactions that still need to be categorised in the For review tab. 

If you're good with your transactions, go ahead and proceed with the steps below:

1. Go to Transactions and select Bank transactions.
2. Select the tile for the bank account.
3. Click the pencil ✎ icon, then select Edit account info.
4. Tick the Disconnect this account on save checkbox.
5. Choose Save and Close.

Once done, reconnect the account at any time to start downloading transactions again.

Moreover, you can also check out this article if you encounter a specific banking error in QBO: Fix bank errors in QuickBooks Online.

Please know that we're open here 24/7, so please don't hesitate to visit us again if you still need more help handling your other banking transactions. The Community always has your back.